Extensible support for tables



Sept. 30, 1958 N. H. MOINNIS EXTENSIBLE SUPPORT FOR TABLES Winn I I I I 1-H. lgxfguilhn FIG.1

INVENTOR. NEIL H. MFINNIS ATTORNEY United States Patent 9 EXTENSIBLE SUPPORT FOR TABLES Neil H. Mclnnis, Flushing, N. Y.

Application September 19, 1957, Serial No. 685,040

5 Claims. (Cl. 311-39) This invention relates to extensible devices, such as table legs or supports, and more particularly to a novel tubular support comprising telescoped tubular sections adjustable as to overall length by relative turning of the sections.

Various extensible support arrangements have been proposed for providing adjustability in the height of tables, stands and the like. These arrangements have incorporated, for example, a guide slot in one section and a guide in another section with suitable provision for locking the guide along the guide slot. As another example, one section has been provided with spring pressed buttons engageable in apertures in the other section. To adjust the length, it has been necessary to manually push in the then active button.

Difiiculty has been experienced with both these arrangements, and with others of a similar nature, due both to malfunctioning after repeated adjustments and also due to complications in effecting the adjustment.

In accordance with the present invention, an adjustable length tubular support is provided comprising a pair of telescoped tubular members one of which has spring pressed buttons riding on a cam surface on an end of the other member. This cam surface has high and low areas engaged by the buttons or plungers in the fully extended and intermediate length positions of the sup port. To select either of these positions, it is necessary merely to rotate the members relative to each other, a releasable thumb screw being provided to lock the members against relative rotation.

The leading ends of the high sections of the cams are provided with wings whose inner surfaces, at their entrance ends, are spaced radially from the plunger carrying member by at least the wall thickness of the cam member. These wings converge inwardly so that their inner surfaces merge with that of the cammed member.

The buttons or plungers are riveted or welded to bowed fiat leaf springs arranged to engage each other when the buttons project through diametrically opposite apertures in the inner member. As the members are relatively rotated to engage the buttons in the cam wings, these latter force the buttons inwardly and ofi the cam surface on the end of the outer member. The support can then be collapsed to its shortest length.

For an understanding of the invention principles, reference is made to the following description of a typical embodiment thereof as illustrated in the accompanying drawing. In the drawing:

Fig. 1 is an elevation view of a table embodying the invention;

Fig. 2 is a top plan view thereof;

Fig. 3 is an enlarged partial elevation view of the central support post;

Figs. 4 and 5 are sectional views on the line 4-4 of Fig. 3 illustrating, respectively, the raised and lowered positions of the table; and

Fig. 6 is an elevation view of the spring and cam follower arrangement.

Patented Sept. 30, 1958 Referring to the drawings, the adjustable support arrangement of the invention is illustrated as incorporated in a table 10 comprising a top 11 bolted, screwed, or otherwise secured to radial arms 12 extending from the upper end of a central tubular support pillar or post generally indicated at 15. Arms 12 may, by way of example, be T-section metal members. The bottom end of pillar or post 15 has integral therewith radial legs 13 which extend outwardly and downwardly and terminate in feet 14.

While the invention is illustrated as embodied in a table supported on a single central pillar 15 having radial arms and legs, it should be understood that pillar 15 is exemplary of adjustable table legs generally and that the invention may be incorporated in a table having two, three, or more adjustable legs 15.

Referring again to pillar or leg 15, this adjustable length member comprises an inner tubular member 16 telescoped in an outer tubular member 17. For a purpose to be described, a thumb screw 18 is threaded into member 17 to selectively engage member 16. Adjustment of the overall length of leg 15 is effected by cam means generally indicated at 20.

Referring to Figs. 3 through 6, the upper end of member 17 is formed with a cam surface cooperable with cam follower buttons 25 extending through apertures 26 in inner member 16 and biased outwardly by bow springs 27 to which buttons 26 are riveted as at 28. Springs 27 have reversely bent outer ends 29 bearing against each other.

The cam surface on the upper end of member 17 has a pair of diametrically opposite valleys 21 engaged by buttons 25 in an intermediate position of members 16, 17, and valleys 21 merge smoothly into diametrically opposite rises 22 engaged by buttons 25 in the fully extended position'of members 16, 17.

The leading ends of rises 22 are formed as wings 23 having their entrance ends spaced from the inner surface of member 17 by at least the thickness of this member. A short distance from their entrance ends, wings 23 converge gradually to the inner surface of member 17 as indicated at 24. Hence, when member 16 is turned clockwise, as viewed in Figs. 4 and 5, buttons 25 engage wings 23 and are moved inwardly by wing surfaces 24 to ride along the inner surface of member 17. This allows post 15 to be collapsed.

if member 16 is turned counter-clockwise from the position of Fig. 4, buttons 25 ride up on cam rises 22 to extend the post. The post 15 is locked in either its intermediate or extended position by tightening thumb screw 18 to prevent relative rotation of members 16 and 17 While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the invention principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. An extensible support for tables or the like comprising, in combination, a pair of relatively elongated telescoped tubular members; one of said members having radially extending buttons spring biased to extend across the inner end surface of the other member; the inner end surface of said other member being formed as a cam surface having valleys engaged by the plungers in the retracted position of the support and hills engaged by the plungers in an intermediate length of the support whereby adjustment of the support length is effected by relative rotation of the members; said inner end surface of said other member having wings extending longitudinally beyond said valleys and having surfaces facing and spaced from the nearest peripheral surface of said one member by at least the wall thickness of said other member to ice engage the ends of said buttons upon selected relative rotation of said members; said wing surface converging toward said nearest peripheral surface of said one member to move said buttons out of engagement with said cam surface upon vcontinued selected relative rotation of said members to allow unrestricted relative axial movement of said members to thefully retracted position of said support; and meansreleasably restrainingsaid membersragainst relative rotation.

2. An extensible support as claimed in claim 1 in which there are a pair of diametrically opposite buttons, a pair of diametrically opposite hills, a pair of diametrically opposite valleys, and a pair of diametrically opposite wings.

3. An extensible support as claimed in claim 2, in which said buttons project through apertures in the inner member intermediate the ends of the latter, said cam surface and wings are on' the outer member, and the buttons are secured to fiat bowed springs within the inner member and having convexly curved ends engaged with each other.

ber intermediate the ends of the latter, and said cam surface and wings are on the-outer member.

References Cited in the file of this patent UNITED STATES'PATENTS 1,133,804 Kaufman Man-30, 1915 1,229,138 Reischmann June 5, 1917 2,628,142 Dubach Feb. 10, 1953 2,659,571 Ferguson Nov. 17, 1953 2,710,048 Dawson June 7, 1955 2,722,970 Stechmann Nov. 8, 1955 2,780,507 Farley Feb.-5, 1957 

